Compression devices for applying compressive forces to a selected area of a wearer's anatomy are generally employed to improve blood flow in the selected area. Compression devices that provide intermittent pulses of a compressed fluid (i.e. air) to inflate at least one inflatable chamber in a cuff or sleeve are particularly useful. This cyclic application of pressure provides a non-invasive method of prophylaxis to reduce the incidence of deep vein thrombosis (DVT), and the like. These compression devices find particular use during surgery on patients with high-risk conditions such as obesity, advanced age, malignancy, or prior thromboembolism. Patients who develop this condition often have swelling (edema) and tissue breakdown (venous stasis ulcer) in the lower leg. When a DVT occurs, the valves that are located within the veins of the leg can be damaged, which in turn can cause stasis and high pressure in the veins of the lower leg.
Generally, these compression devices are fluidly coupled to a source of pressurized fluid by one or more air tubes. Additionally, each compression device includes a flexible shell having one or more bladders disposed therein. The compression device is placed around the patient's foot or other selected portion whereupon a pressurized fluid is delivered into the bladder creating pressure at the part or parts of the body in contact with the bladder.
Compression cuffs adapted for use with a patient's foot may be used by themselves or combined with one or more additional compression cuffs or sleeves that are disposed on portions of a patient's leg for improving the treatment regimen. In general, each of the additional compression sleeves includes a plurality of separate inflatable chambers that are progressively arranged along a longitudinal axis of the sleeve from a lower portion to an upper portion of the limb. A pressure source, e.g. a controller, is provided for intermittently forming a pressure pulse within these inflatable chambers from a source of pressurized fluid during periodic compression cycles. The compression sleeves provide a pressure gradient along the patient's limbs during these compression cycles which progressively decreases from the lower portion to the upper portion of the limb (e.g. from the ankle to the thigh).
Compression cuffs that are adapted for use with a patient's foot generally include a heel strap with a tab portion that is adapted to fit around a portion of the patient's heel. This arrangement allows the compression cuff to be wrapped around and releasably attached to the patient's foot. The compression cuff may include a generally rigid sole to direct expansion of the inflatable chamber toward the wearer's foot. The rigid sole needs to be located under that portion of the inflatable member that is acting on the portion of the foot to produce blood flow out of the foot. Conventionally, the rigid sole is temporarily attached to the bladder by double stick tape. Final location and positioning of the rigid sole may be carried out by stitching. For example, the bladder is typically stitched to an outer wrap of the foot cuff. The stitching can be arranged so that it captures the rigid sole in position relative to the bladder, as well as the outer wrap. This requires care and precision in manufacturing the foot cuff.
Examples of compression cuffs are disclosed in U.S. Pat. Nos. 4,013,069 and 4,030,488 to Hasty, U.S. Pat. Nos. 4,029,087 and 5,795,312 to Dye, U.S. Pat. No. 5,626,556 to Tobler et al., and U.S. patent application Ser. No. 11/761,212 to Meyer et al., all of which are currently owned by Tyco Healthcare Group LP and are incorporated by reference herein in their entireties. Other examples of compression cuffs are disclosed in U.S. Pat. No. 4,696,289 to Gardner et al., U.S. Pat. No. 5,989,204 to Lina and U.S. Pat. No. 5,345,260 to Cook. An example of compression treatment method is disclosed in U.S. Pat. No. 6,231,532 to Watson et al., which is owned by Tyco Healthcare Group LP, the contents of which are hereby incorporated by reference herein in their entirety.